//
// This code is released to the public domain by Jim Studt, 2007.
// He may keep some sort of up to date copy at http://www.federated.com/~jim/canvastext/
//
var CanvasTextFunctions = { };

CanvasTextFunctions.letters = {
	' ': { width: 16, points: [] },
	'!': { width: 10, points: [[5,21],[5,7],[-1,-1],[5,2],[4,1],[5,0],[6,1],[5,2]] },
	'"': { width: 16, points: [[4,21],[4,14],[-1,-1],[12,21],[12,14]] },
	'#': { width: 21, points: [[11,25],[4,-7],[-1,-1],[17,25],[10,-7],[-1,-1],[4,12],[18,12],[-1,-1],[3,6],[17,6]] },
	'$': { width: 20, points: [[8,25],[8,-4],[-1,-1],[12,25],[12,-4],[-1,-1],[17,18],[15,20],[12,21],[8,21],[5,20],[3,18],[3,16],[4,14],[5,13],[7,12],[13,10],[15,9],[16,8],[17,6],[17,3],[15,1],[12,0],[8,0],[5,1],[3,3]] },
	'%': { width: 24, points: [[21,21],[3,0],[-1,-1],[8,21],[10,19],[10,17],[9,15],[7,14],[5,14],[3,16],[3,18],[4,20],[6,21],[8,21],[10,20],[13,19],[16,19],[19,20],[21,21],[-1,-1],[17,7],[15,6],[14,4],[14,2],[16,0],[18,0],[20,1],[21,3],[21,5],[19,7],[17,7]] },
	'&': { width: 26, points: [[23,12],[23,13],[22,14],[21,14],[20,13],[19,11],[17,6],[15,3],[13,1],[11,0],[7,0],[5,1],[4,2],[3,4],[3,6],[4,8],[5,9],[12,13],[13,14],[14,16],[14,18],[13,20],[11,21],[9,20],[8,18],[8,16],[9,13],[11,10],[16,3],[18,1],[20,0],[22,0],[23,1],[23,2]] },
	'\'': { width: 10, points: [[5,19],[4,20],[5,21],[6,20],[6,18],[5,16],[4,15]] },
	'(': { width: 14, points: [[11,25],[9,23],[7,20],[5,16],[4,11],[4,7],[5,2],[7,-2],[9,-5],[11,-7]] },
	')': { width: 14, points: [[3,25],[5,23],[7,20],[9,16],[10,11],[10,7],[9,2],[7,-2],[5,-5],[3,-7]] },
	'*': { width: 16, points: [[8,21],[8,9],[-1,-1],[3,18],[13,12],[-1,-1],[13,18],[3,12]] },
	'+': { width: 26, points: [[13,18],[13,0],[-1,-1],[4,9],[22,9]] },
	',': { width: 10, points: [[6,1],[5,0],[4,1],[5,2],[6,1],[6,-1],[5,-3],[4,-4]] },
	'-': { width: 26, points: [[4,9],[22,9]] },
	'.': { width: 10, points: [[5,2],[4,1],[5,0],[6,1],[5,2]] },
	'/': { width: 22, points: [[20,25],[2,-7]] },
	'0': { width: 20, points: [[9,21],[6,20],[4,17],[3,12],[3,9],[4,4],[6,1],[9,0],[11,0],[14,1],[16,4],[17,9],[17,12],[16,17],[14,20],[11,21],[9,21]] },
	'1': { width: 20, points: [[6,17],[8,18],[11,21],[11,0]] },
	'2': { width: 20, points: [[4,16],[4,17],[5,19],[6,20],[8,21],[12,21],[14,20],[15,19],[16,17],[16,15],[15,13],[13,10],[3,0],[17,0]] },
	'3': { width: 20, points: [[5,21],[16,21],[10,13],[13,13],[15,12],[16,11],[17,8],[17,6],[16,3],[14,1],[11,0],[8,0],[5,1],[4,2],[3,4]] },
	'4': { width: 20, points: [[13,21],[3,7],[18,7],[-1,-1],[13,21],[13,0]] },
	'5': { width: 20, points: [[15,21],[5,21],[4,12],[5,13],[8,14],[11,14],[14,13],[16,11],[17,8],[17,6],[16,3],[14,1],[11,0],[8,0],[5,1],[4,2],[3,4]] },
	'6': { width: 20, points: [[16,18],[15,20],[12,21],[10,21],[7,20],[5,17],[4,12],[4,7],[5,3],[7,1],[10,0],[11,0],[14,1],[16,3],[17,6],[17,7],[16,10],[14,12],[11,13],[10,13],[7,12],[5,10],[4,7]] },
	'7': { width: 20, points: [[17,21],[7,0],[-1,-1],[3,21],[17,21]] },
	'8': { width: 20, points: [[8,21],[5,20],[4,18],[4,16],[5,14],[7,13],[11,12],[14,11],[16,9],[17,7],[17,4],[16,2],[15,1],[12,0],[8,0],[5,1],[4,2],[3,4],[3,7],[4,9],[6,11],[9,12],[13,13],[15,14],[16,16],[16,18],[15,20],[12,21],[8,21]] },
	'9': { width: 20, points: [[16,14],[15,11],[13,9],[10,8],[9,8],[6,9],[4,11],[3,14],[3,15],[4,18],[6,20],[9,21],[10,21],[13,20],[15,18],[16,14],[16,9],[15,4],[13,1],[10,0],[8,0],[5,1],[4,3]] },
	':': { width: 10, points: [[5,14],[4,13],[5,12],[6,13],[5,14],[-1,-1],[5,2],[4,1],[5,0],[6,1],[5,2]] },
	',': { width: 10, points: [[5,14],[4,13],[5,12],[6,13],[5,14],[-1,-1],[6,1],[5,0],[4,1],[5,2],[6,1],[6,-1],[5,-3],[4,-4]] },
	'<': { width: 24, points: [[20,18],[4,9],[20,0]] },
	'=': { width: 26, points: [[4,12],[22,12],[-1,-1],[4,6],[22,6]] },
	'>': { width: 24, points: [[4,18],[20,9],[4,0]] },
	'?': { width: 18, points: [[3,16],[3,17],[4,19],[5,20],[7,21],[11,21],[13,20],[14,19],[15,17],[15,15],[14,13],[13,12],[9,10],[9,7],[-1,-1],[9,2],[8,1],[9,0],[10,1],[9,2]] },
	'@': { width: 27, points: [[18,13],[17,15],[15,16],[12,16],[10,15],[9,14],[8,11],[8,8],[9,6],[11,5],[14,5],[16,6],[17,8],[-1,-1],[12,16],[10,14],[9,11],[9,8],[10,6],[11,5],[-1,-1],[18,16],[17,8],[17,6],[19,5],[21,5],[23,7],[24,10],[24,12],[23,15],[22,17],[20,19],[18,20],[15,21],[12,21],[9,20],[7,19],[5,17],[4,15],[3,12],[3,9],[4,6],[5,4],[7,2],[9,1],[12,0],[15,0],[18,1],[20,2],[21,3],[-1,-1],[19,16],[18,8],[18,6],[19,5]] },
	'A': { width: 18, points: [[9,21],[1,0],[-1,-1],[9,21],[17,0],[-1,-1],[4,7],[14,7]] },
	'B': { width: 21, points: [[4,21],[4,0],[-1,-1],[4,21],[13,21],[16,20],[17,19],[18,17],[18,15],[17,13],[16,12],[13,11],[-1,-1],[4,11],[13,11],[16,10],[17,9],[18,7],[18,4],[17,2],[16,1],[13,0],[4,0]] },
	'C': { width: 21, points: [[18,16],[17,18],[15,20],[13,21],[9,21],[7,20],[5,18],[4,16],[3,13],[3,8],[4,5],[5,3],[7,1],[9,0],[13,0],[15,1],[17,3],[18,5]] },
	'D': { width: 21, points: [[4,21],[4,0],[-1,-1],[4,21],[11,21],[14,20],[16,18],[17,16],[18,13],[18,8],[17,5],[16,3],[14,1],[11,0],[4,0]] },
	'E': { width: 19, points: [[4,21],[4,0],[-1,-1],[4,21],[17,21],[-1,-1],[4,11],[12,11],[-1,-1],[4,0],[17,0]] },
	'F': { width: 18, points: [[4,21],[4,0],[-1,-1],[4,21],[17,21],[-1,-1],[4,11],[12,11]] },
	'G': { width: 21, points: [[18,16],[17,18],[15,20],[13,21],[9,21],[7,20],[5,18],[4,16],[3,13],[3,8],[4,5],[5,3],[7,1],[9,0],[13,0],[15,1],[17,3],[18,5],[18,8],[-1,-1],[13,8],[18,8]] },
	'H': { width: 22, points: [[4,21],[4,0],[-1,-1],[18,21],[18,0],[-1,-1],[4,11],[18,11]] },
	'I': { width: 8, points: [[4,21],[4,0]] },
	'J': { width: 16, points: [[12,21],[12,5],[11,2],[10,1],[8,0],[6,0],[4,1],[3,2],[2,5],[2,7]] },
	'K': { width: 21, points: [[4,21],[4,0],[-1,-1],[18,21],[4,7],[-1,-1],[9,12],[18,0]] },
	'L': { width: 17, points: [[4,21],[4,0],[-1,-1],[4,0],[16,0]] },
	'M': { width: 24, points: [[4,21],[4,0],[-1,-1],[4,21],[12,0],[-1,-1],[20,21],[12,0],[-1,-1],[20,21],[20,0]] },
	'N': { width: 22, points: [[4,21],[4,0],[-1,-1],[4,21],[18,0],[-1,-1],[18,21],[18,0]] },
	'O': { width: 22, points: [[9,21],[7,20],[5,18],[4,16],[3,13],[3,8],[4,5],[5,3],[7,1],[9,0],[13,0],[15,1],[17,3],[18,5],[19,8],[19,13],[18,16],[17,18],[15,20],[13,21],[9,21]] },
	'P': { width: 21, points: [[4,21],[4,0],[-1,-1],[4,21],[13,21],[16,20],[17,19],[18,17],[18,14],[17,12],[16,11],[13,10],[4,10]] },
	'Q': { width: 22, points: [[9,21],[7,20],[5,18],[4,16],[3,13],[3,8],[4,5],[5,3],[7,1],[9,0],[13,0],[15,1],[17,3],[18,5],[19,8],[19,13],[18,16],[17,18],[15,20],[13,21],[9,21],[-1,-1],[12,4],[18,-2]] },
	'R': { width: 21, points: [[4,21],[4,0],[-1,-1],[4,21],[13,21],[16,20],[17,19],[18,17],[18,15],[17,13],[16,12],[13,11],[4,11],[-1,-1],[11,11],[18,0]] },
	'S': { width: 20, points: [[17,18],[15,20],[12,21],[8,21],[5,20],[3,18],[3,16],[4,14],[5,13],[7,12],[13,10],[15,9],[16,8],[17,6],[17,3],[15,1],[12,0],[8,0],[5,1],[3,3]] },
	'T': { width: 16, points: [[8,21],[8,0],[-1,-1],[1,21],[15,21]] },
	'U': { width: 22, points: [[4,21],[4,6],[5,3],[7,1],[10,0],[12,0],[15,1],[17,3],[18,6],[18,21]] },
	'V': { width: 18, points: [[1,21],[9,0],[-1,-1],[17,21],[9,0]] },
	'W': { width: 24, points: [[2,21],[7,0],[-1,-1],[12,21],[7,0],[-1,-1],[12,21],[17,0],[-1,-1],[22,21],[17,0]] },
	'X': { width: 20, points: [[3,21],[17,0],[-1,-1],[17,21],[3,0]] },
	'Y': { width: 18, points: [[1,21],[9,11],[9,0],[-1,-1],[17,21],[9,11]] },
	'Z': { width: 20, points: [[17,21],[3,0],[-1,-1],[3,21],[17,21],[-1,-1],[3,0],[17,0]] },
	'[': { width: 14, points: [[4,25],[4,-7],[-1,-1],[5,25],[5,-7],[-1,-1],[4,25],[11,25],[-1,-1],[4,-7],[11,-7]] },
	'\\': { width: 14, points: [[0,21],[14,-3]] },
	']': { width: 14, points: [[9,25],[9,-7],[-1,-1],[10,25],[10,-7],[-1,-1],[3,25],[10,25],[-1,-1],[3,-7],[10,-7]] },
	'^': { width: 16, points: [[6,15],[8,18],[10,15],[-1,-1],[3,12],[8,17],[13,12],[-1,-1],[8,17],[8,0]] },
	'_': { width: 16, points: [[0,-2],[16,-2]] },
	'`': { width: 10, points: [[6,21],[5,20],[4,18],[4,16],[5,15],[6,16],[5,17]] },
	'a': { width: 19, points: [[15,14],[15,0],[-1,-1],[15,11],[13,13],[11,14],[8,14],[6,13],[4,11],[3,8],[3,6],[4,3],[6,1],[8,0],[11,0],[13,1],[15,3]] },
	'b': { width: 19, points: [[4,21],[4,0],[-1,-1],[4,11],[6,13],[8,14],[11,14],[13,13],[15,11],[16,8],[16,6],[15,3],[13,1],[11,0],[8,0],[6,1],[4,3]] },
	'c': { width: 18, points: [[15,11],[13,13],[11,14],[8,14],[6,13],[4,11],[3,8],[3,6],[4,3],[6,1],[8,0],[11,0],[13,1],[15,3]] },
	'd': { width: 19, points: [[15,21],[15,0],[-1,-1],[15,11],[13,13],[11,14],[8,14],[6,13],[4,11],[3,8],[3,6],[4,3],[6,1],[8,0],[11,0],[13,1],[15,3]] },
	'e': { width: 18, points: [[3,8],[15,8],[15,10],[14,12],[13,13],[11,14],[8,14],[6,13],[4,11],[3,8],[3,6],[4,3],[6,1],[8,0],[11,0],[13,1],[15,3]] },
	'f': { width: 12, points: [[10,21],[8,21],[6,20],[5,17],[5,0],[-1,-1],[2,14],[9,14]] },
	'g': { width: 19, points: [[15,14],[15,-2],[14,-5],[13,-6],[11,-7],[8,-7],[6,-6],[-1,-1],[15,11],[13,13],[11,14],[8,14],[6,13],[4,11],[3,8],[3,6],[4,3],[6,1],[8,0],[11,0],[13,1],[15,3]] },
	'h': { width: 19, points: [[4,21],[4,0],[-1,-1],[4,10],[7,13],[9,14],[12,14],[14,13],[15,10],[15,0]] },
	'i': { width: 8, points: [[3,21],[4,20],[5,21],[4,22],[3,21],[-1,-1],[4,14],[4,0]] },
	'j': { width: 10, points: [[5,21],[6,20],[7,21],[6,22],[5,21],[-1,-1],[6,14],[6,-3],[5,-6],[3,-7],[1,-7]] },
	'k': { width: 17, points: [[4,21],[4,0],[-1,-1],[14,14],[4,4],[-1,-1],[8,8],[15,0]] },
	'l': { width: 8, points: [[4,21],[4,0]] },
	'm': { width: 30, points: [[4,14],[4,0],[-1,-1],[4,10],[7,13],[9,14],[12,14],[14,13],[15,10],[15,0],[-1,-1],[15,10],[18,13],[20,14],[23,14],[25,13],[26,10],[26,0]] },
	'n': { width: 19, points: [[4,14],[4,0],[-1,-1],[4,10],[7,13],[9,14],[12,14],[14,13],[15,10],[15,0]] },
	'o': { width: 19, points: [[8,14],[6,13],[4,11],[3,8],[3,6],[4,3],[6,1],[8,0],[11,0],[13,1],[15,3],[16,6],[16,8],[15,11],[13,13],[11,14],[8,14]] },
	'p': { width: 19, points: [[4,14],[4,-7],[-1,-1],[4,11],[6,13],[8,14],[11,14],[13,13],[15,11],[16,8],[16,6],[15,3],[13,1],[11,0],[8,0],[6,1],[4,3]] },
	'q': { width: 19, points: [[15,14],[15,-7],[-1,-1],[15,11],[13,13],[11,14],[8,14],[6,13],[4,11],[3,8],[3,6],[4,3],[6,1],[8,0],[11,0],[13,1],[15,3]] },
	'r': { width: 13, points: [[4,14],[4,0],[-1,-1],[4,8],[5,11],[7,13],[9,14],[12,14]] },
	's': { width: 17, points: [[14,11],[13,13],[10,14],[7,14],[4,13],[3,11],[4,9],[6,8],[11,7],[13,6],[14,4],[14,3],[13,1],[10,0],[7,0],[4,1],[3,3]] },
	't': { width: 12, points: [[5,21],[5,4],[6,1],[8,0],[10,0],[-1,-1],[2,14],[9,14]] },
	'u': { width: 19, points: [[4,14],[4,4],[5,1],[7,0],[10,0],[12,1],[15,4],[-1,-1],[15,14],[15,0]] },
	'v': { width: 16, points: [[2,14],[8,0],[-1,-1],[14,14],[8,0]] },
	'w': { width: 22, points: [[3,14],[7,0],[-1,-1],[11,14],[7,0],[-1,-1],[11,14],[15,0],[-1,-1],[19,14],[15,0]] },
	'x': { width: 17, points: [[3,14],[14,0],[-1,-1],[14,14],[3,0]] },
	'y': { width: 16, points: [[2,14],[8,0],[-1,-1],[14,14],[8,0],[6,-4],[4,-6],[2,-7],[1,-7]] },
	'z': { width: 17, points: [[14,14],[3,0],[-1,-1],[3,14],[14,14],[-1,-1],[3,0],[14,0]] },
	'{': { width: 14, points: [[9,25],[7,24],[6,23],[5,21],[5,19],[6,17],[7,16],[8,14],[8,12],[6,10],[-1,-1],[7,24],[6,22],[6,20],[7,18],[8,17],[9,15],[9,13],[8,11],[4,9],[8,7],[9,5],[9,3],[8,1],[7,0],[6,-2],[6,-4],[7,-6],[-1,-1],[6,8],[8,6],[8,4],[7,2],[6,1],[5,-1],[5,-3],[6,-5],[7,-6],[9,-7]] },
	'|': { width: 8, points: [[4,25],[4,-7]] },
	'}': { width: 14, points: [[5,25],[7,24],[8,23],[9,21],[9,19],[8,17],[7,16],[6,14],[6,12],[8,10],[-1,-1],[7,24],[8,22],[8,20],[7,18],[6,17],[5,15],[5,13],[6,11],[10,9],[6,7],[5,5],[5,3],[6,1],[7,0],[8,-2],[8,-4],[7,-6],[-1,-1],[8,8],[6,6],[6,4],[7,2],[8,1],[9,-1],[9,-3],[8,-5],[7,-6],[5,-7]] },
	'~': { width: 24, points: [[3,6],[3,8],[4,11],[6,12],[8,12],[10,11],[14,8],[16,7],[18,7],[20,8],[21,10],[-1,-1],[3,8],[4,10],[6,11],[8,11],[10,10],[14,7],[16,6],[18,6],[20,7],[21,10],[21,12]] }
};

CanvasTextFunctions.letter = function(ch) {
	return CanvasTextFunctions.letters[ch];
}

CanvasTextFunctions.ascent = function(font, size) {
	return size;
}

CanvasTextFunctions.descent = function(font, size) {
	return 7.0 * size / 25.0;
}

CanvasTextFunctions.measure = function(font, size, str) {
	var total = 0;
	var len = str.length;
	
	for (i = 0; i < len; i++) {
		var c = CanvasTextFunctions.letter(str.charAt(i));
		if (c) 
			total += c.width * size / 25.0;
	}
	return total;
}

CanvasTextFunctions.draw = function(ctx, font, size, x, y, str) {
	var total = 0;
	var len = str.length;
	var mag = size / 25.0;
	
	ctx.save();
	ctx.lineCap = "round";
	ctx.lineWidth = 2.0 * mag;
	
	for (i = 0; i < len; i++) {
		var c = CanvasTextFunctions.letter(str.charAt(i));
		if (!c) 
			continue;
		
		ctx.beginPath();
		
		var penUp = 1;
		var needStroke = 0;
		for (j = 0; j < c.points.length; j++) {
			var a = c.points[j];
			if (a[0] == -1 && a[1] == -1) {
				penUp = 1;
				continue;
			}
			if (penUp) {
				ctx.moveTo(x + a[0] * mag, y - a[1] * mag);
				penUp = false;
			} else {
				ctx.lineTo(x + a[0] * mag, y - a[1] * mag);
			}
		}
		ctx.stroke();
		x += c.width * mag;
	}
	ctx.restore();
	return total;
}

CanvasTextFunctions.enable = function(ctx) {
	ctx.drawText = function(font, size, x, y, text) {
		return CanvasTextFunctions.draw(ctx, font, size, x, y, text);
	};
	ctx.measureText = function(font, size, text) {
		return CanvasTextFunctions.measure(font, size, text);
	};
	ctx.fontAscent = function(font, size) {
		return CanvasTextFunctions.ascent(font, size);
	}
	ctx.fontDescent = function(font, size) {
		return CanvasTextFunctions.descent(font, size);
	}
	
	ctx.drawTextRight = function(font, size, x, y, text) {
		var w = CanvasTextFunctions.measure(font, size, text);
		return CanvasTextFunctions.draw(ctx, font, size, x - w, y, text);
	};
	ctx.drawTextCenter = function(font, size, x, y, text) {
		var w = CanvasTextFunctions.measure(font, size, text);
		return CanvasTextFunctions.draw(ctx, font, size, x - w / 2, y, text);
	};
}
